This invention relates generally to couplings for electrical conduits or the like and more particularly to an improved swivel connector.
In attaching a connector for electrical conduits containing electrical conductors to outlet boxes, limit switches, control boxes, etc., the connector must be threaded tightly, but not too tightly or the threads would strip. It is also a common requirement of the coupling means of the type to which the present invention is directed, that a seal be provided as well as good electrical grounding. In association with many types of tools, machinery, equipment, etc., liquids are used for lubrication, cooling, cleaning and cutting. The liquids are often splased on the electrical connections. Additionally, moisture in the air could enter the conduit via the smallest opening in the connector or coupling and be condensed and trapped in threads therein, thus enhancing corrosion and poor electrical connections. Any liquid that is present in the conduit could possibly short out the conductors.
Examples of prior art in the general field to which the present invention is directed are disclosed in U.S. Pat. Nos. 3,710,911 and 3,828,117 as well as Canadian Pat. No. 944,404. A feature common to the two U.S. patents. is a tubular body member having an inner sleeve of rigid, plastic material which protrudes slightly beyond the ends of a body member. A pair of nuts are slidably mounted on the outer, peripheral surface of the tubular body member between outwardly directed radial flanges that are adjacent opposite ends of the body member. The nuts are threaded onto the ends of axially opposed conduits. The Canadian patent, which is particuarly directed to an angled connector, utilizes the concept of a rigid plastic, inner sleeve and similarly provides a liquid-tight connection. The three patents discussed hereinabove provide a structure that may be readily disassembled. In addition, the structure in the three prior art patents just discussed provide a swivel characteristic wherein a length of conduit may be connected without having to rotate any section of the conduit while still providing seal means that will assure a fluid-tight coupling.